dccp.h 15 KB

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  1. #ifndef _LINUX_DCCP_H
  2. #define _LINUX_DCCP_H
  3. #include <linux/types.h>
  4. #include <asm/byteorder.h>
  5. /**
  6. * struct dccp_hdr - generic part of DCCP packet header
  7. *
  8. * @dccph_sport - Relevant port on the endpoint that sent this packet
  9. * @dccph_dport - Relevant port on the other endpoint
  10. * @dccph_doff - Data Offset from the start of the DCCP header, in 32-bit words
  11. * @dccph_ccval - Used by the HC-Sender CCID
  12. * @dccph_cscov - Parts of the packet that are covered by the Checksum field
  13. * @dccph_checksum - Internet checksum, depends on dccph_cscov
  14. * @dccph_x - 0 = 24 bit sequence number, 1 = 48
  15. * @dccph_type - packet type, see DCCP_PKT_ prefixed macros
  16. * @dccph_seq - sequence number high or low order 24 bits, depends on dccph_x
  17. */
  18. struct dccp_hdr {
  19. __be16 dccph_sport,
  20. dccph_dport;
  21. __u8 dccph_doff;
  22. #if defined(__LITTLE_ENDIAN_BITFIELD)
  23. __u8 dccph_cscov:4,
  24. dccph_ccval:4;
  25. #elif defined(__BIG_ENDIAN_BITFIELD)
  26. __u8 dccph_ccval:4,
  27. dccph_cscov:4;
  28. #else
  29. #error "Adjust your <asm/byteorder.h> defines"
  30. #endif
  31. __sum16 dccph_checksum;
  32. #if defined(__LITTLE_ENDIAN_BITFIELD)
  33. __u8 dccph_x:1,
  34. dccph_type:4,
  35. dccph_reserved:3;
  36. #elif defined(__BIG_ENDIAN_BITFIELD)
  37. __u8 dccph_reserved:3,
  38. dccph_type:4,
  39. dccph_x:1;
  40. #else
  41. #error "Adjust your <asm/byteorder.h> defines"
  42. #endif
  43. __u8 dccph_seq2;
  44. __be16 dccph_seq;
  45. };
  46. /**
  47. * struct dccp_hdr_ext - the low bits of a 48 bit seq packet
  48. *
  49. * @dccph_seq_low - low 24 bits of a 48 bit seq packet
  50. */
  51. struct dccp_hdr_ext {
  52. __be32 dccph_seq_low;
  53. };
  54. /**
  55. * struct dccp_hdr_request - Conection initiation request header
  56. *
  57. * @dccph_req_service - Service to which the client app wants to connect
  58. * @dccph_req_options - list of options (must be a multiple of 32 bits
  59. */
  60. struct dccp_hdr_request {
  61. __be32 dccph_req_service;
  62. };
  63. /**
  64. * struct dccp_hdr_ack_bits - acknowledgment bits common to most packets
  65. *
  66. * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  67. * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  68. */
  69. struct dccp_hdr_ack_bits {
  70. __be16 dccph_reserved1;
  71. __be16 dccph_ack_nr_high;
  72. __be32 dccph_ack_nr_low;
  73. };
  74. /**
  75. * struct dccp_hdr_response - Conection initiation response header
  76. *
  77. * @dccph_resp_ack_nr_high - 48 bit ack number high order bits, contains GSR
  78. * @dccph_resp_ack_nr_low - 48 bit ack number low order bits, contains GSR
  79. * @dccph_resp_service - Echoes the Service Code on a received DCCP-Request
  80. * @dccph_resp_options - list of options (must be a multiple of 32 bits
  81. */
  82. struct dccp_hdr_response {
  83. struct dccp_hdr_ack_bits dccph_resp_ack;
  84. __be32 dccph_resp_service;
  85. };
  86. /**
  87. * struct dccp_hdr_reset - Unconditionally shut down a connection
  88. *
  89. * @dccph_reset_service - Echoes the Service Code on a received DCCP-Request
  90. * @dccph_reset_options - list of options (must be a multiple of 32 bits
  91. */
  92. struct dccp_hdr_reset {
  93. struct dccp_hdr_ack_bits dccph_reset_ack;
  94. __u8 dccph_reset_code,
  95. dccph_reset_data[3];
  96. };
  97. enum dccp_pkt_type {
  98. DCCP_PKT_REQUEST = 0,
  99. DCCP_PKT_RESPONSE,
  100. DCCP_PKT_DATA,
  101. DCCP_PKT_ACK,
  102. DCCP_PKT_DATAACK,
  103. DCCP_PKT_CLOSEREQ,
  104. DCCP_PKT_CLOSE,
  105. DCCP_PKT_RESET,
  106. DCCP_PKT_SYNC,
  107. DCCP_PKT_SYNCACK,
  108. DCCP_PKT_INVALID,
  109. };
  110. #define DCCP_NR_PKT_TYPES DCCP_PKT_INVALID
  111. static inline unsigned int dccp_packet_hdr_len(const __u8 type)
  112. {
  113. if (type == DCCP_PKT_DATA)
  114. return 0;
  115. if (type == DCCP_PKT_DATAACK ||
  116. type == DCCP_PKT_ACK ||
  117. type == DCCP_PKT_SYNC ||
  118. type == DCCP_PKT_SYNCACK ||
  119. type == DCCP_PKT_CLOSE ||
  120. type == DCCP_PKT_CLOSEREQ)
  121. return sizeof(struct dccp_hdr_ack_bits);
  122. if (type == DCCP_PKT_REQUEST)
  123. return sizeof(struct dccp_hdr_request);
  124. if (type == DCCP_PKT_RESPONSE)
  125. return sizeof(struct dccp_hdr_response);
  126. return sizeof(struct dccp_hdr_reset);
  127. }
  128. enum dccp_reset_codes {
  129. DCCP_RESET_CODE_UNSPECIFIED = 0,
  130. DCCP_RESET_CODE_CLOSED,
  131. DCCP_RESET_CODE_ABORTED,
  132. DCCP_RESET_CODE_NO_CONNECTION,
  133. DCCP_RESET_CODE_PACKET_ERROR,
  134. DCCP_RESET_CODE_OPTION_ERROR,
  135. DCCP_RESET_CODE_MANDATORY_ERROR,
  136. DCCP_RESET_CODE_CONNECTION_REFUSED,
  137. DCCP_RESET_CODE_BAD_SERVICE_CODE,
  138. DCCP_RESET_CODE_TOO_BUSY,
  139. DCCP_RESET_CODE_BAD_INIT_COOKIE,
  140. DCCP_RESET_CODE_AGGRESSION_PENALTY,
  141. };
  142. /* DCCP options */
  143. enum {
  144. DCCPO_PADDING = 0,
  145. DCCPO_MANDATORY = 1,
  146. DCCPO_MIN_RESERVED = 3,
  147. DCCPO_MAX_RESERVED = 31,
  148. DCCPO_CHANGE_L = 32,
  149. DCCPO_CONFIRM_L = 33,
  150. DCCPO_CHANGE_R = 34,
  151. DCCPO_CONFIRM_R = 35,
  152. DCCPO_NDP_COUNT = 37,
  153. DCCPO_ACK_VECTOR_0 = 38,
  154. DCCPO_ACK_VECTOR_1 = 39,
  155. DCCPO_TIMESTAMP = 41,
  156. DCCPO_TIMESTAMP_ECHO = 42,
  157. DCCPO_ELAPSED_TIME = 43,
  158. DCCPO_MAX = 45,
  159. DCCPO_MIN_CCID_SPECIFIC = 128,
  160. DCCPO_MAX_CCID_SPECIFIC = 255,
  161. };
  162. /* DCCP CCIDS */
  163. enum {
  164. DCCPC_CCID2 = 2,
  165. DCCPC_CCID3 = 3,
  166. };
  167. /* DCCP features (RFC 4340 section 6.4) */
  168. enum {
  169. DCCPF_RESERVED = 0,
  170. DCCPF_CCID = 1,
  171. DCCPF_SHORT_SEQNOS = 2, /* XXX: not yet implemented */
  172. DCCPF_SEQUENCE_WINDOW = 3,
  173. DCCPF_ECN_INCAPABLE = 4, /* XXX: not yet implemented */
  174. DCCPF_ACK_RATIO = 5,
  175. DCCPF_SEND_ACK_VECTOR = 6,
  176. DCCPF_SEND_NDP_COUNT = 7,
  177. DCCPF_MIN_CSUM_COVER = 8,
  178. DCCPF_DATA_CHECKSUM = 9, /* XXX: not yet implemented */
  179. /* 10-127 reserved */
  180. DCCPF_MIN_CCID_SPECIFIC = 128,
  181. DCCPF_MAX_CCID_SPECIFIC = 255,
  182. };
  183. /* this structure is argument to DCCP_SOCKOPT_CHANGE_X */
  184. struct dccp_so_feat {
  185. __u8 dccpsf_feat;
  186. __u8 __user *dccpsf_val;
  187. __u8 dccpsf_len;
  188. };
  189. /* DCCP socket options */
  190. #define DCCP_SOCKOPT_PACKET_SIZE 1 /* XXX deprecated, without effect */
  191. #define DCCP_SOCKOPT_SERVICE 2
  192. #define DCCP_SOCKOPT_CHANGE_L 3
  193. #define DCCP_SOCKOPT_CHANGE_R 4
  194. #define DCCP_SOCKOPT_SEND_CSCOV 10
  195. #define DCCP_SOCKOPT_RECV_CSCOV 11
  196. #define DCCP_SOCKOPT_CCID_RX_INFO 128
  197. #define DCCP_SOCKOPT_CCID_TX_INFO 192
  198. /* maximum number of services provided on the same listening port */
  199. #define DCCP_SERVICE_LIST_MAX_LEN 32
  200. #ifdef __KERNEL__
  201. #include <linux/in.h>
  202. #include <linux/ktime.h>
  203. #include <linux/list.h>
  204. #include <linux/uio.h>
  205. #include <linux/workqueue.h>
  206. #include <net/inet_connection_sock.h>
  207. #include <net/inet_sock.h>
  208. #include <net/inet_timewait_sock.h>
  209. #include <net/tcp_states.h>
  210. enum dccp_state {
  211. DCCP_OPEN = TCP_ESTABLISHED,
  212. DCCP_REQUESTING = TCP_SYN_SENT,
  213. DCCP_PARTOPEN = TCP_FIN_WAIT1, /* FIXME:
  214. This mapping is horrible, but TCP has
  215. no matching state for DCCP_PARTOPEN,
  216. as TCP_SYN_RECV is already used by
  217. DCCP_RESPOND, why don't stop using TCP
  218. mapping of states? OK, now we don't use
  219. sk_stream_sendmsg anymore, so doesn't
  220. seem to exist any reason for us to
  221. do the TCP mapping here */
  222. DCCP_LISTEN = TCP_LISTEN,
  223. DCCP_RESPOND = TCP_SYN_RECV,
  224. DCCP_CLOSING = TCP_CLOSING,
  225. DCCP_TIME_WAIT = TCP_TIME_WAIT,
  226. DCCP_CLOSED = TCP_CLOSE,
  227. DCCP_MAX_STATES = TCP_MAX_STATES,
  228. };
  229. #define DCCP_STATE_MASK 0xf
  230. #define DCCP_ACTION_FIN (1<<7)
  231. enum {
  232. DCCPF_OPEN = TCPF_ESTABLISHED,
  233. DCCPF_REQUESTING = TCPF_SYN_SENT,
  234. DCCPF_PARTOPEN = TCPF_FIN_WAIT1,
  235. DCCPF_LISTEN = TCPF_LISTEN,
  236. DCCPF_RESPOND = TCPF_SYN_RECV,
  237. DCCPF_CLOSING = TCPF_CLOSING,
  238. DCCPF_TIME_WAIT = TCPF_TIME_WAIT,
  239. DCCPF_CLOSED = TCPF_CLOSE,
  240. };
  241. static inline struct dccp_hdr *dccp_hdr(const struct sk_buff *skb)
  242. {
  243. return (struct dccp_hdr *)skb_transport_header(skb);
  244. }
  245. static inline struct dccp_hdr *dccp_zeroed_hdr(struct sk_buff *skb, int headlen)
  246. {
  247. skb_push(skb, headlen);
  248. skb_reset_transport_header(skb);
  249. return memset(skb_transport_header(skb), 0, headlen);
  250. }
  251. static inline struct dccp_hdr_ext *dccp_hdrx(const struct sk_buff *skb)
  252. {
  253. return (struct dccp_hdr_ext *)(skb_transport_header(skb) +
  254. sizeof(struct dccp_hdr));
  255. }
  256. static inline unsigned int __dccp_basic_hdr_len(const struct dccp_hdr *dh)
  257. {
  258. return sizeof(*dh) + (dh->dccph_x ? sizeof(struct dccp_hdr_ext) : 0);
  259. }
  260. static inline unsigned int dccp_basic_hdr_len(const struct sk_buff *skb)
  261. {
  262. const struct dccp_hdr *dh = dccp_hdr(skb);
  263. return __dccp_basic_hdr_len(dh);
  264. }
  265. static inline __u64 dccp_hdr_seq(const struct sk_buff *skb)
  266. {
  267. const struct dccp_hdr *dh = dccp_hdr(skb);
  268. __u64 seq_nr = ntohs(dh->dccph_seq);
  269. if (dh->dccph_x != 0)
  270. seq_nr = (seq_nr << 32) + ntohl(dccp_hdrx(skb)->dccph_seq_low);
  271. else
  272. seq_nr += (u32)dh->dccph_seq2 << 16;
  273. return seq_nr;
  274. }
  275. static inline struct dccp_hdr_request *dccp_hdr_request(struct sk_buff *skb)
  276. {
  277. return (struct dccp_hdr_request *)(skb_transport_header(skb) +
  278. dccp_basic_hdr_len(skb));
  279. }
  280. static inline struct dccp_hdr_ack_bits *dccp_hdr_ack_bits(const struct sk_buff *skb)
  281. {
  282. return (struct dccp_hdr_ack_bits *)(skb_transport_header(skb) +
  283. dccp_basic_hdr_len(skb));
  284. }
  285. static inline u64 dccp_hdr_ack_seq(const struct sk_buff *skb)
  286. {
  287. const struct dccp_hdr_ack_bits *dhack = dccp_hdr_ack_bits(skb);
  288. return ((u64)ntohs(dhack->dccph_ack_nr_high) << 32) + ntohl(dhack->dccph_ack_nr_low);
  289. }
  290. static inline struct dccp_hdr_response *dccp_hdr_response(struct sk_buff *skb)
  291. {
  292. return (struct dccp_hdr_response *)(skb_transport_header(skb) +
  293. dccp_basic_hdr_len(skb));
  294. }
  295. static inline struct dccp_hdr_reset *dccp_hdr_reset(struct sk_buff *skb)
  296. {
  297. return (struct dccp_hdr_reset *)(skb_transport_header(skb) +
  298. dccp_basic_hdr_len(skb));
  299. }
  300. static inline unsigned int __dccp_hdr_len(const struct dccp_hdr *dh)
  301. {
  302. return __dccp_basic_hdr_len(dh) +
  303. dccp_packet_hdr_len(dh->dccph_type);
  304. }
  305. static inline unsigned int dccp_hdr_len(const struct sk_buff *skb)
  306. {
  307. return __dccp_hdr_len(dccp_hdr(skb));
  308. }
  309. /* initial values for each feature */
  310. #define DCCPF_INITIAL_SEQUENCE_WINDOW 100
  311. #define DCCPF_INITIAL_ACK_RATIO 2
  312. #define DCCPF_INITIAL_CCID DCCPC_CCID2
  313. #define DCCPF_INITIAL_SEND_ACK_VECTOR 1
  314. /* FIXME: for now we're default to 1 but it should really be 0 */
  315. #define DCCPF_INITIAL_SEND_NDP_COUNT 1
  316. #define DCCP_NDP_LIMIT 0xFFFFFF
  317. /**
  318. * struct dccp_minisock - Minimal DCCP connection representation
  319. *
  320. * Will be used to pass the state from dccp_request_sock to dccp_sock.
  321. *
  322. * @dccpms_sequence_window - Sequence Window Feature (section 7.5.2)
  323. * @dccpms_ccid - Congestion Control Id (CCID) (section 10)
  324. * @dccpms_send_ack_vector - Send Ack Vector Feature (section 11.5)
  325. * @dccpms_send_ndp_count - Send NDP Count Feature (7.7.2)
  326. * @dccpms_ack_ratio - Ack Ratio Feature (section 11.3)
  327. * @dccpms_pending - List of features being negotiated
  328. * @dccpms_conf -
  329. */
  330. struct dccp_minisock {
  331. __u64 dccpms_sequence_window;
  332. __u8 dccpms_rx_ccid;
  333. __u8 dccpms_tx_ccid;
  334. __u8 dccpms_send_ack_vector;
  335. __u8 dccpms_send_ndp_count;
  336. __u8 dccpms_ack_ratio;
  337. struct list_head dccpms_pending;
  338. struct list_head dccpms_conf;
  339. };
  340. struct dccp_opt_conf {
  341. __u8 *dccpoc_val;
  342. __u8 dccpoc_len;
  343. };
  344. struct dccp_opt_pend {
  345. struct list_head dccpop_node;
  346. __u8 dccpop_type;
  347. __u8 dccpop_feat;
  348. __u8 *dccpop_val;
  349. __u8 dccpop_len;
  350. int dccpop_conf;
  351. struct dccp_opt_conf *dccpop_sc;
  352. };
  353. extern void __dccp_minisock_init(struct dccp_minisock *dmsk);
  354. extern void dccp_minisock_init(struct dccp_minisock *dmsk);
  355. extern int dccp_parse_options(struct sock *sk, struct sk_buff *skb);
  356. struct dccp_request_sock {
  357. struct inet_request_sock dreq_inet_rsk;
  358. __u64 dreq_iss;
  359. __u64 dreq_isr;
  360. __be32 dreq_service;
  361. };
  362. static inline struct dccp_request_sock *dccp_rsk(const struct request_sock *req)
  363. {
  364. return (struct dccp_request_sock *)req;
  365. }
  366. extern struct inet_timewait_death_row dccp_death_row;
  367. struct dccp_options_received {
  368. u32 dccpor_ndp; /* only 24 bits */
  369. u32 dccpor_timestamp;
  370. u32 dccpor_timestamp_echo;
  371. u32 dccpor_elapsed_time;
  372. };
  373. struct ccid;
  374. enum dccp_role {
  375. DCCP_ROLE_UNDEFINED,
  376. DCCP_ROLE_LISTEN,
  377. DCCP_ROLE_CLIENT,
  378. DCCP_ROLE_SERVER,
  379. };
  380. struct dccp_service_list {
  381. __u32 dccpsl_nr;
  382. __be32 dccpsl_list[0];
  383. };
  384. #define DCCP_SERVICE_INVALID_VALUE htonl((__u32)-1)
  385. #define DCCP_SERVICE_CODE_IS_ABSENT 0
  386. static inline int dccp_list_has_service(const struct dccp_service_list *sl,
  387. const __be32 service)
  388. {
  389. if (likely(sl != NULL)) {
  390. u32 i = sl->dccpsl_nr;
  391. while (i--)
  392. if (sl->dccpsl_list[i] == service)
  393. return 1;
  394. }
  395. return 0;
  396. }
  397. struct dccp_ackvec;
  398. /**
  399. * struct dccp_sock - DCCP socket state
  400. *
  401. * @dccps_swl - sequence number window low
  402. * @dccps_swh - sequence number window high
  403. * @dccps_awl - acknowledgement number window low
  404. * @dccps_awh - acknowledgement number window high
  405. * @dccps_iss - initial sequence number sent
  406. * @dccps_isr - initial sequence number received
  407. * @dccps_osr - first OPEN sequence number received
  408. * @dccps_gss - greatest sequence number sent
  409. * @dccps_gsr - greatest valid sequence number received
  410. * @dccps_gar - greatest valid ack number received on a non-Sync; initialized to %dccps_iss
  411. * @dccps_service - first (passive sock) or unique (active sock) service code
  412. * @dccps_service_list - second .. last service code on passive socket
  413. * @dccps_timestamp_time - time of latest TIMESTAMP option
  414. * @dccps_timestamp_echo - latest timestamp received on a TIMESTAMP option
  415. * @dccps_l_ack_ratio - feature-local Ack Ratio
  416. * @dccps_r_ack_ratio - feature-remote Ack Ratio
  417. * @dccps_pcslen - sender partial checksum coverage (via sockopt)
  418. * @dccps_pcrlen - receiver partial checksum coverage (via sockopt)
  419. * @dccps_ndp_count - number of Non Data Packets since last data packet
  420. * @dccps_mss_cache - current value of MSS (path MTU minus header sizes)
  421. * @dccps_minisock - associated minisock (accessed via dccp_msk)
  422. * @dccps_hc_rx_ackvec - rx half connection ack vector
  423. * @dccps_hc_rx_ccid - CCID used for the receiver (or receiving half-connection)
  424. * @dccps_hc_tx_ccid - CCID used for the sender (or sending half-connection)
  425. * @dccps_options_received - parsed set of retrieved options
  426. * @dccps_role - role of this sock, one of %dccp_role
  427. * @dccps_hc_rx_insert_options - receiver wants to add options when acking
  428. * @dccps_hc_tx_insert_options - sender wants to add options when sending
  429. * @dccps_xmit_timer - timer for when CCID is not ready to send
  430. * @dccps_syn_rtt - RTT sample from Request/Response exchange (in usecs)
  431. */
  432. struct dccp_sock {
  433. /* inet_connection_sock has to be the first member of dccp_sock */
  434. struct inet_connection_sock dccps_inet_connection;
  435. #define dccps_syn_rtt dccps_inet_connection.icsk_ack.lrcvtime
  436. __u64 dccps_swl;
  437. __u64 dccps_swh;
  438. __u64 dccps_awl;
  439. __u64 dccps_awh;
  440. __u64 dccps_iss;
  441. __u64 dccps_isr;
  442. __u64 dccps_osr;
  443. __u64 dccps_gss;
  444. __u64 dccps_gsr;
  445. __u64 dccps_gar;
  446. __be32 dccps_service;
  447. struct dccp_service_list *dccps_service_list;
  448. ktime_t dccps_timestamp_time;
  449. __u32 dccps_timestamp_echo;
  450. __u16 dccps_l_ack_ratio;
  451. __u16 dccps_r_ack_ratio;
  452. __u16 dccps_pcslen;
  453. __u16 dccps_pcrlen;
  454. unsigned long dccps_ndp_count;
  455. __u32 dccps_mss_cache;
  456. struct dccp_minisock dccps_minisock;
  457. struct dccp_ackvec *dccps_hc_rx_ackvec;
  458. struct ccid *dccps_hc_rx_ccid;
  459. struct ccid *dccps_hc_tx_ccid;
  460. struct dccp_options_received dccps_options_received;
  461. enum dccp_role dccps_role:2;
  462. __u8 dccps_hc_rx_insert_options:1;
  463. __u8 dccps_hc_tx_insert_options:1;
  464. struct timer_list dccps_xmit_timer;
  465. };
  466. static inline struct dccp_sock *dccp_sk(const struct sock *sk)
  467. {
  468. return (struct dccp_sock *)sk;
  469. }
  470. static inline struct dccp_minisock *dccp_msk(const struct sock *sk)
  471. {
  472. return (struct dccp_minisock *)&dccp_sk(sk)->dccps_minisock;
  473. }
  474. static inline const char *dccp_role(const struct sock *sk)
  475. {
  476. switch (dccp_sk(sk)->dccps_role) {
  477. case DCCP_ROLE_UNDEFINED: return "undefined";
  478. case DCCP_ROLE_LISTEN: return "listen";
  479. case DCCP_ROLE_SERVER: return "server";
  480. case DCCP_ROLE_CLIENT: return "client";
  481. }
  482. return NULL;
  483. }
  484. #endif /* __KERNEL__ */
  485. #endif /* _LINUX_DCCP_H */